Wellbore isolation needs arise in many contexts and a variety of sealing designs have been used to meet this need. Packers are run in to a desired location and then set with mechanical force or hydraulic pressure to extend slips for anchoring and a sealing element for sealing. Some packers are inflated to a sealing position using tubing pressure.
Another type of isolation device is the cup seal. One such design shown in U.S. Pat. No. 4,424,865 uses the basic elastomer cup shape and includes a base and internal fingers of a shape memory alloy so that upon exposure to heat above a predetermined temperature, the ribs get stiffer and move the cup outwardly against the surrounding tubular to enhance the seal. Packer cups have also been formed out of a shape memory polymer and reformed before run in to a smaller cup shape. After getting to the desired location the temperature exceeds a predetermined level and the shape reverts to an original shape that results in operative engagement of the cup seal with the surrounding tubular. Variations of this design are shown in US Publication 2012/0055667 FIGS. 13-15.
US Publication 2012/0055667 FIGS. 13-15 forms the cup shape for run in but with the rim of the cup being smaller than the inside diameter of the surrounding tubular. In deviated wellbores the rim is exposed to being dragged on the inside wall of the surrounding tubular which can cause the cup to either rip or invert if its open end is oriented in the same direction as for run in. The present invention addresses this issue with a run in shape that is preferably cylindrical or up against the mandrel that supports the cup. End rings are provided that have a slightly larger dimension than the cup run in dimension so that any dragging on a surrounding tubular such as with a deviated well will not abrade the cup while still allowing the cup the ability to assume the original shape with a thermal stimulus and seal in the wellbore. As another option there can be elongated members that are affixed to the mandrel or end ring at one end and have the opposite end free. They can also protect the cup during delivery and can be further covered with retainer material to keep the components in their respective positions for run in without adversely affecting the ability to hold differential pressure once actuated. These and other aspects of the present invention will be more readily apparent to one of ordinary skill in the art from a review of the detailed description of the preferred embodiment and the associated drawings while recognizing that the full scope of the invention is to be determined by the appended claims.